The animals have even been dubbed "zombie dogs," and police are warning residents to stay far away from the typically nocturnal animals.

The coyotes are actually infected with sarcoptic mange, which can make their appearance seem weakened and sickly, police in Hanover Park, Ill. say.

This stock image shows a coyote staring directly at a camera. Hanover Park, Ill. police have said mangy coyotes can look like some sort of “zombie dog.” (LeFion/Getty Images/iStockphoto)

A Facebook post from their department reads, "Recently we have received several messages and posts from citizens concerned about what appear to be malnourished or neglected stray dogs. These are NOT lost pets, but are in fact coyotes."

They say there has been an increase in the disease among the urban coyote population. It is making the animals come out during the day, as well.

These infected coyotes could appear hairless and frail.

Cops say they're not normally aggressive but should still be avoided. They also warn residents to keep their pets away from the mange-infected animals.

The department advises residents to secure garbage cans and avoid leaving any sort of food outside.

Even with the threat, though, the Cook County urban coyote ecology and management website says that there hasn't been a single coyote attack, according to NBC 5.

Someone is more likely to get bit by a domestic dog, the site suggests.